Responses of four yeast genes to changes in the transcriptional machinery are determined by their promoters.

Many yeast genes are distinguished by their specific requirements for different components of the transcriptional machinery. Here we examine four genes that fall into two classes as defined by their dependence on specific components of the transcriptional machinery. We describe a series of hybrid constructs, each of which bears activator binding sites that are associated with a promoter other than that with which they are usually affiliated. We examine expression of these reporters in strains bearing three modifications of the transcriptional machinery. Our results indicate that, in each of these cases, the promoter (and not the activator) determines which components of the transcriptional machinery are required. These and additional results, including those of others, clarify how disparate activators can work at many different promoters.